(I don't know where to put this thread)

Does anyone know of a mod that makes the game have no time limit?

Do you mean, the number of turns of a game?
This is set in the Civ4GameSpeedInfo.xml, where, for each speed, you set how many turns a game lasts, and their correspondant date increment. If you want a game to last forever (!!), just set the last entry of iTurnsPerIncrement to a very large number.

A more simple way is to disable the "Time Victory" option when creating a customized game. ;)